Gordon Deborah M
Department of Biological Sciences, Stanford University, 94305-5020, Stanford, CA, USA.
Oecologia. 1993 Oct;95(4):479-487. doi: 10.1007/BF00317431.
Colonies of the seed-eating ant, Pogonomyrmex barbatus, compete with neighboring colonies for foraging areas. In a conflict over foraging area, what is at stake? This depends on how resources are distributed in time and space: if certain regions consistently provide particularly nutritious seed species, or especially abundant seeds, such regions will be of greater value to a colony. During the summer, seeds were taken from returning foragers in colonies located in 4 different vegetation types. There was no relation between the vegetation currently growing in the foraging area, and the species of seeds collected by ants. During the summer, ants collect mostly seeds produced in previous seasons and dispersed by wind and flooding. In 1991, colonies in all vegetation types collected mostly Bouteloua aristidoides; in 1992, Eriastrum diffusum and Plantago patagonica. There was no relation between colony density and numbers of seeds collected. Seed species collected by ants were compared in different colonies, and on different foraging trails within a colony. The results show that seed patches are distributed on the scale of distances between nests, not the smaller scale of different foraging trails of one colony. It appears that colonies are competing for any space in which to search for seeds, not competing for certain regions of consistently high value.
以种子为食的巴氏收获蚁（Pogonomyrmex barbatus）群体与邻近群体争夺觅食区域。在觅食区域的冲突中，利害关系是什么？这取决于资源在时间和空间上的分布情况：如果某些区域持续提供特别有营养的种子种类，或者种子特别丰富，那么这些区域对一个群体来说价值就更大。在夏季，从位于4种不同植被类型中的蚁群的归巢觅食蚁那里采集种子。觅食区域当前生长的植被与蚂蚁采集的种子种类之间没有关联。在夏季，蚂蚁主要采集上一季产生并通过风和洪水传播的种子。1991年，所有植被类型中的蚁群大多采集糙隐子草（Bouteloua aristidoides）；1992年，大多采集散生绵果菊（Eriastrum diffusum）和巴塔哥尼亚车前（Plantago patagonica）。蚁群密度与采集的种子数量之间没有关联。对不同蚁群以及一个蚁群内不同觅食路径上蚂蚁采集的种子种类进行了比较。结果表明，种子斑块是在巢穴之间的距离尺度上分布的，而不是在一个蚁群不同觅食路径的较小尺度上分布。看来蚁群是在争夺任何可用于寻找种子的空间，而不是在争夺某些价值持续很高的特定区域。
